Machine for making blade envelopes



Nov. 14, 1961 E. A STALKER ET AI. MACHINE FOR MAKING BLADE ENVELOPES 4 Sheets-Sheet 1 Filed Jan. 3. 1957 INVENTORS EDWARD A. STALKER ATTORNEYS DANIEL J. CLARKE MM Mw 4 Sheets-Sheet 2 INVENTORJ' EDWARD A. STALKER DANIEL J. CLARKE ATTORNEYS E. A. STALKER ETA].

MACHINE FOR MAKING BLADE ENVELOPES Nov. 14, 1961 Filed Jan. 5/ 1957 l l I Nov. 14, 1961 E. A. STALKER ETAL 3,008,509

MACHINE FOR MAKING BLADE ENVELOPES Filed Jan. 3. 1957 4 Sheets-Sheet 3 INVHVTORS A. STALKER EL J. CLARKE ATTORNEYS Nov. 14, 1961 E. A. STALKER ET AL 3,

- MACHINE FOR MAKING BLADE ENVELOPES Filed Jan. 3, 1957 4 Sheets-Sheet 4 FIG-6 INVENTORQ EDWARD A. STALKER 8 DANIEL J. CLARKE ATTORN EYS the end of its stroke.

studs 41.

guide posts 44 which pass through bearings in the die United States Patent f" This invention relates tothe making of hollow blades for compressors, turbines and the like and its object is to.

provide a machine for stretch forming the envelopes or shells of such blades.

Other objects and advantages will appear from the specification, accompanying drawings and appended claims.

In the drawings which disclose a preferred embodiment of the invention, in which-f- FIG. 1 is a side elevation of the machine'for forming the envelopes or shells of blades according to this invention; 1

FIG. 2 is a top plan view of the machine of FIG. 1; 7

FIG. 3 is a horizontal section on line 33 of FIG. '5; FIG. 4 is a plan viewof a blade blank with the cleats or stops secured to the side edges thereof; I

FIG-'5 is a side elevation of the machine partly in section; v

- FIG. 6 isa perspective view of the blank as it comes from the press;

FIG. 7 is a perspective view of the male die; and

FIG. 8 is an end elevational view of the .blank after the side edges have been trimmed ofi.

The machine is indicated generally as 10 in FIG. 1. It comprises a male die 12 and a female dieassembly having contoured wall surfaces on die members 14 and 15 supported in operable relation v'vitha recess 20 therebe tween so that the male die can be advanced against a blade blank16 positioned on the ends -of the dies and lying across the recess 20.

As shown in FIGS. 1, 2 and the male die is advanced fully without a blade blank inthe machine. In FIG. 3 the male die is in its most advanced position with a blade blank in place and has stretched the blank so that it has taken on the proper shape from the dies. To accomplish the stretching the blank is restrained by cleats 24 preferably spot-welded to the blank forming positive stops. As the male die advances the cleats are drawn inward until they are seated against the abutments 26 and 28. This seating occurs before the male die reaches Further movement of the male die causes stretching of the metal of the blank as it is formed over the contoured walls 'of the female dies.

In FIG. 5 the frame of the press is indicated as 30 including'upper horizontal arms 32 integral with the lower horizontal members 34. These support'the vertical end member 36 fixed to the upper arms 32 and thelower members '34, respectively.

The base plate 40 is fixed to the end member 36 and the female die members 14 and 15 are fixed to itby The base plate 40 supports four horizontal plate 46 and guide the latter. The male die is fixed' to the die plate and derives its stroke from the movement of the plate.

The male die and die plate are reciprocated' by a piston in cylinder -50.

ened to the stud '55 of male die 12 by-means of-pin 56 with die plate 46 therebetweenf The reciprocating motion of the rod is controlled by admitting fluid pressure alternately. to opposite ends of the cylinder through pipes 60 and 62 and valve 64 controlled by handle 66. The

60 hence the links 96, 98'and'assoc1ated'cam mechanism can be of relatively lightweight construction.

Its piston rod 52 is suitably fixedto the drive rod 54 and the forward end of rod 54 is'fastat 90, 92 respectively in the frame 94'. The cam folthereof 'over. the die faces. vided for engaging the lateral edges of the blank after 3,008,509 Patented Nov. 14, 1961 pipes 68 and 70 conduct fluid to and from a source of fluid under pressure.

It has been found desirable toallow relatively free movement of the blade blankon' its support in the initial portion of the forming operation but to firmly secure the blank along its side edges in the latterportion of the operation, in order to assure the desired stretch forming Accordingly means is prothe .male die has operated over the initial portion of its stroke and for positively holding the same against 'movement for the remainder of the stroke. "For this purpose the drive rod'54 is-formedwith cam blocks 100, 102 on opposite sides thereof and'such cam blocksengage and actuatea pair of rollers 82, 84, mountedon opposite sides of the rod in cam follower members 86, 88, pivoted lower members are connected to links 96; 98 by pivots 97 and to brackets 99 fastened to the body of abutment .therethrough without interference.

block 80 by pivots 97a. 'The latter has a central aperture to receive the male die 12,allowing the same to operate On its working face the abutment block carries hardened replaceable inserts 110 which are formed with right-angle notches 26, 28 adapted to engage the stops 24 'of the blank. As will be clear from FIG.. 4, such stops extend preferably throughout the length of the blank and along both sides edges thereof, the notches on the lower face of inserts 110 being similarly shaped so that a positive engagement along both lateral edgesiof the blank isassured.

In order to provide for return movement of the abutment block 80. after the working stroke, the die plate '46 has notches on its opposite-sidesv through which thelinks 96' and 98 pass freely,-and outwardly thereof the plate carries straps 115 which are adapted to engage with pins 1'16 fixed'in the respective links in the final withdrawing movement of'the drive rod.

. In operation, a flat piece of sheet 'metal16 has the cleats or stops 24'spot-Weldedthereto and is placed in position on the end of the female die extending across recess. 20,: any suitable'means suchas vertical st'ops z-5 of restraining force, and thus allowing the sheet to'be forced into the female die recess; As the stroke proceeds, the rise on cam blocks 100, 102 will actuate cams 8'6, 88 v and thereby advance abutment block 80 into the position shown in FIG. 3 such thatthe notches 26, 28 on insert 110. intercept and positively stop further lateral travel of thesides of the blank. Since this occurs before 1 the end of the stroke of the male'die, the remaining travel of the latter results in stretch forming of the metal over therespective die surfaces. The final travel of the male die'is controlled by the-provision of stops 120 on abutment block 80 upon which lateral projections of the male die bear to thus accurately fix the-limit of its forward travel. While the sheet is being stretched-the cleats secure the edges without significant axial force being applied and Further the force of the hydraulic fluid "in the cylinder is not dissipated by the holding operation and since the cleats bear in opposite directions on the abutment block the forces developed therein are balanced and confined to the block itself without being transmitted to the remainder of the press. I 'The abutment block is preferably a unitary'ele Whileqthe form of, apparatus, herein described constitutes. a preferred embodiment ofthe invention, it is to be understood that the invention is not limited to this pre- .,cise form of'apparatus, and. that changes may be made :therein without departing from the scope of the invention vwhich is defined in the a-ppended claims.

w What is, claimed is:

1--. ,A machine forvstretch formingblades for compressors, turbinesand the like'from a. flat sheet metal 7 blankprovided with cleats along the lateral edges there- ,of which comprises :female die members having a recess z-therebetween with walls ofpredeterminedcontour and .-1adapted to receive-the blankat the end thereof extending across said recess, a male'die shaped to engage said blank and to force the same ,intoisaid recess for preforming the desired bladeshape over-said contoured die Walls, an abutzwmentblock movable with saiddie toward and away from said blankand having means thereon vadapted to engage 'saidlcleats; means for advancingsaid male die and abutment block-on a working stroke,zlinkage means controlling themovement of said abutment block means relative tosaid male zdie, into the path of said cleats leaving said blank: substantially free, of. restraining force during van initialportioniofgthe travel, offlsaid male die and said blockzandforeffecting, positive stopping of said lateral edges of the blank by said block in the latter portion of the travel of said die to. effect a final stretch forming of \saidblank, and means provided on'said linkage means for retracting; said: abutment, block following said working stroke of said linkage control. means. 1

2. A machine for, stretch forming blades for compressors, turbines and the .like 'f-romafiat sheet metal blank which comprises fem-ale .die members having a recess therebetween' with walls of predetermined contour.

and: adaptedto receive the blank at the .end thereof and extending across said recess, a male die. shaped tosengage said blank and to force the same'intosaidrecessfor preforming the desired blade shape over said contoured die walls with the lateral edges of the blank supported freely, an abutment block movable with saidLdie toward and away from said blank and having opposite retaining means thereon adapted to engage; sm'd, blank along opposite lateral edges thereof, power means fr advancing said male die and abutment blockon a Working stroke, operating means for advancing said abutment block one time -cycle different from that of said. die advancing means to" establish engagement of said block with said lateral edges .of said'blank at a predetermined point after the male die has:enteredsaid die-membersrwith resultant final stretch forming ofthehblank over said contoured wall surfaces,

and means provided on saidpoweradvancingrneans for 'retracting'said abutment block following said movement of said male die away-from said blank.

3. A machine for stretch forming blades forv com- 4 adapted to engage said opposite stops on said blank, means for advancingsaid male die and abutment block on a working stroke, operating means controlling the movement of said abutment block into engagement with said blank following engagement of said male die with said blank leaving said blanksubstantially free of restraining force duringan initial portion of.the travel of said male die and for effecting engagement between said block and said stops in the latter portionof the travel of said die to effect final stretch forming of said blank with the stretching forces on saidretaining means beingcarried by said block in directions transverse to the direction of movement of said abutment block with opposition of one said ,;.stretching force to theother, and means provided on said advancing means for retracting said abutment block following said workingistroke of said advancing means.

4. A machine for stretch forming blades for compressors, turbines andtthe like from a flat sheet metal blank having. s'topston. theopposite lateral edges thereof which comprises female die members having a recess therebetween with walls of predetermined contour andadapted to receive the blank at the-end thereof and extending across said recess, a male die shaped to engage said blank and movable on a working stroke to force the same into said recess for preforming the desired blade shape over said contoured die walls and movable away from'said t .blank for disengagement therefrom, an abutment block movable with said die toward and away from said blank and having means thereon adapted to engage said stops on said blank, power means for advancing said male die and abutment block on a working stroke, operating means for'advancing said abutment block on a working stroke on a time cycle different from that of said die advancing means to establish engagement with said blank stops at apredetermined point in the metal forming portion of the working stroke of said male die with resultant final stretch forming of the blank over said contoured wall surfaces, and means provided on said power advancing means for retracting said abutment block following said movement of said male die away from said blank.

- 5. -A' machine for stretch forming bladesfor compressors, turbines and the like from a flat sheet metalblank having stops along the opposite lateral edges thereof -whichcomprises female die' members having, a recess therebetween with walls of predetermined contour and adapted to-receive the blank at the end thereof extending across said recess, said stops extending outwardly of the major surface ofsaid blank, a male die shaped to engage said blank and movable on a working stroke to force the same into said recess for preforming the desired blade'shapeover said contoured die walls, an abutment blockjmovable with'said die toward and away from said blank and having means thereon adapted to engage the stops on said blank, power means. for advancing said male die and abutment block on a working stroke, operating means arranged in balanced relation for advancing. said abutment block after a predetermined part of the. metal forming stroke of saidimale die to a'position to intercept said stops in the final portion of the travel of said male die, and means provided on said power advancing means for retracting said abutment block followingsaidwlorking stroke of said operating means.

pressors, turbines and the like from a flatysheet metal blank having stepson the opposite later-a1 ,edges thereof ,which. comprises female, die members having a recess pihf6b6lCW6I1lWlbh walls of predetermined contour-and adapted to receive the blank at the end thereof-extending tacrosssaid .recess,,,said stops extending outwardly of the majonsurface of said blank, a male dieshaped to engage v-said blank and to force the same into said recess for .pre-

forming the desired blade shape over said contoured die :walls wi-ththelateral .edgesof the blank supported freely, u an abutment block movable :with said die toward and away from said blank and having retaining means thereon 6. A'machinefor stretch forming blades for compres- --sors, turbines and the like from a flat sheet metal blank havingv stops along the opposite lateral edges thereof iwhichcomprises-female die members having a recess therebetween with walls of predetermined contour and adapted to receive the blank at the end thereof extending across said recess, said stops extending outwardly of .the major surface of said blank, a male die shaped to engagesaid blank and. movable on a working-stroke to v force the same into said recess for preforming the desired ;:blade shape over said contoured die walls, an abutment -;bl0ck movable with said die toward and away from said blank and having means thereon adapted to engage the stops on said blank, power means. for advancing said male die and abutment block on a metal working stroke including a drive rod, means having a connection to said drive rod operable after said male die has engaged and preformed said blank to effect advance of said abutment block into a position loosely engaging said blank and a position to intercept said stops thereon at a predetermined point in advance of the end of said working stroke, and additional means operatively connected with said abutment block for retracting the same following said work ing stroke thereof.

7. A machine for stretch forming blades for compressors, turbines and the like from a flat sheet metal blank having stops along the opposite lateral edges thereof which comprises female die members having a recess therebetween with walls of predetermined contour and adapted to receive the blank at the end thereof extending across said recess, a male die shaped to engage said blank and movable on a working stroke to force the same into said recess for preforming the desired blade shape over said contoured die Walls, an abutment block movable with said die toward and away from said blank and having opposite retaining means thereon adapted to engage the stops on said blank, power means for advancing said male die and male die insuring that said blank is free of restraining forces at said lateral edges while it is being drawn into said recess by said male die over a predetermined portion of its stroke and that said edges are restrained over the remaining portion of said stroke of said male die to effect stretch forming of said blank on said dies, and means for retracting said block on the return stroke of said drive rod to release said blank.

References Cited in the file of this patent UNITED STATES PATENTS 1,530,000 Kaufirnan Mar. 17, 1925 1,622,590 Jolstad Mar. 29, 1927 2,257,383 .iohansen Sept. 30, 1941 2,579,078 Johansen Dec. 18, 1951 2,880,496

Benedict Apr. 7, 1959 

